反倾层状岩质边坡块状–弯曲倾倒变形演化过程试验研究  

Experimental study on block-flexure toppling deformation evolution process of anti-dip layered rock slopes

作　　者：龚逸非 姚爱军[1] 李彦霖 朱淳 李慧[1] GONG Yifei;YAO Aijun;LI Yanlin;ZHU Chun;LI Hui(Faculty of Architecture,Civil and Transportation Engineering,Beijing University of Technology,Beijing 100124,China;Hohai University School of Earth Sciences and Engineering,Nanjing,Jiangsu 211100,China)

机构地区：[1]北京工业大学城市建设学部,北京100124 [2]河海大学地球科学与工程学院,江苏南京211100

出　　处：《岩石力学与工程学报》2024年第10期2497-2510,共14页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家重点研发计划项目(2022YFC3080100);国家自然科学基金资助项目(52104125,52374119)。

摘　　要：为研究三江并流地区某反倾岩质边坡在复杂内外动力共同作用下的倾倒变形破坏机制,开展相似材料物理模型试验并着重研究反倾岩质边坡在构造应力、河流快速下切以及降雨条件下发生块状–弯曲倾倒变形失稳的各阶段演化过程。结合离散元数值试验分析边坡岩层在各工况下的宏观变形特征、关键点的位移变化规律、最大弯折面的演化、岩层塑性区的分布等。结果表明:(1)试验与模拟结果吻合较好,倾倒变形演化过程分为坡趾剪切弯曲→出现最大弯折面→弯折面上部岩层弯曲倾倒→主破裂面贯通4个阶段;(2)坡趾区域首先发生浅层块状倾倒,伴随最大弯折面的贯通,弯折面上部岩层呈现叠网状的深层弯曲倾倒,下部岩层则相对稳定,体现反倾岩层的自稳性特征;(3)河流下切作用是反倾岩质边坡形成弯曲倾倒变形的前提条件,而降雨作用加快了倾倒体从蠕变阶段向累进破坏阶段的过渡,最终导致岩层发生倾倒失稳。In order to study the toppling deformation and failure mechanism of an anti-dip rock slope in the Three Parallel Rivers area under the combined action of complex internal and external forces.The physical model test of similar materials is carried out,and the evolution process of block-flexure toppling deformation and instability of the anti-dip rock slope under tectonic stress,rapid river downcutting and rainfall conditions is studied.Combined with the discrete element numerical test,the macroscopic deformation characteristics of the slope rock stratum under various working conditions,the displacement variation law of the key points,the evolution of the maximum flexure surface,and the distribution of the plastic zone of the rock stratum are analysed.The results show that:(1) The test results are in good agreement with the simulation results.The evolution process of toppling deformation is divided into four stages:shear flexure of slope toe→maximum flexure surface→flexure and toppling of rock strata under flexure surface→penetration of main fracture surface.(2) The shallow block toppling first occurs in the slope toe area.With the penetration of the maximum flexure surface,the lower strata of the flexure surface show a deep flexure toppling of the laminated network,and the upper strata are relatively stable,which reflects the self-stability characteristics of the anti-dip rock slope.(3) River undercutting is a prerequisite for the formation of flexure toppling deformation of anti-dip rock slope,and rainfall aggravates the transition of toppling body from creep stage to progressive failure stage,which eventually leads to toppling instability of rock strata.

关 键 词：边坡工程 反倾岩质边坡 块状–弯曲倾倒 外部加载 演化过程 破坏机制 

分 类 号：P642[天文地球—工程地质学]